Field of the Invention
The present invention relates to a system, apparatus, method and recording medium for processing an image and, in particular, to a system, apparatus, method and recording medium for extracting a feature from the image.
Description of the Related Art
Japanese Unexamined Patent Application Publication No. 2004-62868 discloses functions of detecting a face, extracting a feature of an image, and retrieving the image in small consumer electronics (CE) such as digital still camera
Since processors mounted on a typical small CE are limited in performance, an image can be analyzed within a limited area. The image cannot be analyzed sufficiently. Analysis results provide insufficient accuracy level and find limited applications.
Detection of human faces requires a long period of time unless definition of an image to be analyzed is set to be low. Process time substantially exceeds time available for typical users. If the definition of an image is set to be too low, it is difficult to detect a face image of a small size, particularly, a face image of a person in a group photo. The low-definition image thus cannot satisfy a need for retrieving a particular face on a group photo.
For example, if the above-discussed analysis process is performed on a digital still camera, the camera must focus on that process and power consumption increases. Time available for image capturing is shortened, and the number of frames of image is reduced.
Digital still cameras are now in widespread use, and many digital still camera functions are transferred to cellular phones. In daily life, the opportunity of (still) picture capturing is substantially increased. If a user attempts to view captured images on a digital still camera, only reduced images (thumb-nail images) are available in the order of image capturing in retrieval process. In image retrieval performance, the digital still camera is substantially outperformed by a computer provided with an image management program.